下面是一个函数，根据powtac的答案将秒转换为hh-mm-ss格式

斯菲德尔

/** 
 * Convert seconds to hh-mm-ss format.
 * @param {number} totalSeconds - the total seconds to convert to hh- mm-ss
**/
var SecondsTohhmmss = function(totalSeconds) {
  var hours   = Math.floor(totalSeconds / 3600);
  var minutes = Math.floor((totalSeconds - (hours * 3600)) / 60);
  var seconds = totalSeconds - (hours * 3600) - (minutes * 60);

  // round seconds
  seconds = Math.round(seconds * 100) / 100

  var result = (hours < 10 ? "0" + hours : hours);
      result += "-" + (minutes < 10 ? "0" + minutes : minutes);
      result += "-" + (seconds  < 10 ? "0" + seconds : seconds);
  return result;
}

示例使用

var seconds = SecondsTohhmmss(70);
console.log(seconds);
// logs 00-01-10

var sec_to_hms = function(sec){
var min, hours;
     sec = sec - (min = Math.floor(sec/60))*60;
     min = min - (hours = Math.floor(min/60))*60;
     return (hours?hours+':':'') + ((min+'').padStart(2, '0')) + ':'+ ((sec+'').padStart(2, '0'));
}
alert(sec_to_hms(2442542));

var time1 = date1.getTime();
var time2 = date2.getTime();
var totalMilisec = time2 - time1;

alert(DateFormat('hh:mm:ss',new Date(totalMilisec)))

 /* ----------------------------------------------------------
 *  Field        | Full Form          | Short Form
 *  -------------|--------------------|-----------------------
 *  Year         | yyyy (4 digits)    | yy (2 digits)
 *  Month        | MMM (abbr.)        | MM (2 digits)
                 | NNN (name)         |
 *  Day of Month | dd (2 digits)      | 
 *  Day of Week  | EE (name)          | E (abbr)
 *  Hour (1-12)  | hh (2 digits)      | 
 *  Minute       | mm (2 digits)      | 
 *  Second       | ss (2 digits)      | 
 *  ----------------------------------------------------------
 */
function DateFormat(formatString,date){
    if (typeof date=='undefined'){
    var DateToFormat=new Date();
    }
    else{
        var DateToFormat=date;
    }
    var DAY         = DateToFormat.getDate();
    var DAYidx      = DateToFormat.getDay();
    var MONTH       = DateToFormat.getMonth()+1;
    var MONTHidx    = DateToFormat.getMonth();
    var YEAR        = DateToFormat.getYear();
    var FULL_YEAR   = DateToFormat.getFullYear();
    var HOUR        = DateToFormat.getHours();
    var MINUTES     = DateToFormat.getMinutes();
    var SECONDS     = DateToFormat.getSeconds();

    var arrMonths = new Array("January","February","March","April","May","June","July","August","September","October","November","December");
    var arrDay=new Array('Sunday','Monday','Tuesday','Wednesday','Thursday','Friday','Saturday');
    var strMONTH;
    var strDAY;
    var strHOUR;
    var strMINUTES;
    var strSECONDS;
    var Separator;

    if(parseInt(MONTH)< 10 && MONTH.toString().length < 2)
        strMONTH = "0" + MONTH;
    else
        strMONTH=MONTH;
    if(parseInt(DAY)< 10 && DAY.toString().length < 2)
        strDAY = "0" + DAY;
    else
        strDAY=DAY;
    if(parseInt(HOUR)< 10 && HOUR.toString().length < 2)
        strHOUR = "0" + HOUR;
    else
        strHOUR=HOUR;
    if(parseInt(MINUTES)< 10 && MINUTES.toString().length < 2)
        strMINUTES = "0" + MINUTES;
    else
        strMINUTES=MINUTES;
    if(parseInt(SECONDS)< 10 && SECONDS.toString().length < 2)
        strSECONDS = "0" + SECONDS;
    else
        strSECONDS=SECONDS;

    switch (formatString){
        case "hh:mm:ss":
            return strHOUR + ':' + strMINUTES + ':' + strSECONDS;
        break;
        //More cases to meet your requirements.
    }
}

export const secondsToHHMMSS = (seconds) => {
  const HH = `${Math.floor(seconds / 3600)}`.padStart(2, '0');
  const MM = `${Math.floor(seconds / 60) % 60}`.padStart(2, '0');
  const SS = `${Math.floor(seconds % 60)}`.padStart(2, '0');
  return [HH, MM, SS].join(':');
};

简单的函数转换秒为hh:mm:ss格式:

function getHHMMSSFromSeconds(totalSeconds) {
    if (!totalSeconds) {
      return '00:00:00';
    }
    const hours = Math.floor(totalSeconds / 3600);
    const minutes = Math.floor(totalSeconds % 3600 / 60);
    const seconds = totalSeconds % 60;
    const hhmmss = padTo2(hours) + ':' + padTo2(minutes) + ':' + padTo2(seconds);
    return hhmmss;
}

// function to convert single digit to double digit
function padTo2(value) {
    if (!value) {
      return '00';
    }
    return value < 10 ? String(value).padStart(2, '0') : value;
}

正如Cleiton在他的回答中指出的，moment.js可以用于:

moment().startOf('day')
        .seconds(15457)
        .format('H:mm:ss');